Polyamide and preparation method thereof
阅读说明:本技术 一种聚酰胺及其制备方法 (Polyamide and preparation method thereof ) 是由 杨冬 李东阵 于 2021-06-28 设计创作,主要内容包括:本发明提供了一种聚酰胺及其制备方法,其中聚酰胺PA XY/XZ由下述组分聚合而成:X为含有8到14个碳原子的不含侧链的脂肪族二胺;Y为含有4到10个碳原子的不含侧链的脂肪族二酸,且X中碳原子总数比Y中碳原子总数至少多于2;Z为芳族二羧酸或/和脂肪环状二羧酸或/和它们的混合物;聚酰胺PA XY/XZ中XY摩尔分数为40-100%,XZ摩尔分数为0-60%,XY和XZ摩尔含量总和为100%。此外本发明还涉及包含所述聚酰胺的组合物和制品。(The invention provides polyamide and a preparation method thereof, wherein the polyamide PA XY/XZ is polymerized by the following components: x is an aliphatic diamine containing 8 to 14 carbon atoms and no side chain; y is a non-pendant aliphatic diacid containing from 4 to 10 carbon atoms and the total number of carbon atoms in X is at least more than 2 than the total number of carbon atoms in Y; z is an aromatic dicarboxylic acid or/and an aliphatic cyclic dicarboxylic acid or/and mixtures thereof; the XY mole fraction of the polyamide PA XY/XZ is 40-100%, the XZ mole fraction is 0-60%, and the total of the XY and XZ mole contents is 100%. The invention also relates to compositions and articles comprising said polyamide.)
1. Polyamide PA XY/XZ, characterized in that the polyamide is polymerized from:
x is an aliphatic diamine containing 8 to 14 carbon atoms and no side chain;
y is a pendant-free aliphatic dicarboxylic acid containing 4 to 10 carbon atoms, and the total number of carbon atoms in X is at least 2 more than the total number of carbon atoms in Y;
z is an aromatic dicarboxylic acid or/and an aliphatic cyclic dicarboxylic acid.
2. The polyamide PA XY/XZ according to claim 1, characterized in that the molar content of component XY is from 40 to 100%, the molar content of component XZ is from 0 to 60%, the molar contents of components XY and XZ together adding up to 100%.
3. Polyamide PA XY/XZ according to claim 1 or 2, characterized in that the ratio of the molar amount of dicarboxylic acid to the molar amount of diamine in the component is 1.04:1 to 1: 1.04.
4. the polyamide PA XY/XZ according to claim 1, characterized in that the aromatic dicarboxylic acid is selected from one or more of terephthalic acid, 4' -biphenyldicarboxylic acid, 2, 6-naphthalenedicarboxylic acid; the aliphatic cyclic dicarboxylic acid is 1, 4-cyclohexanedicarboxylic acid.
5. Process for the preparation of the polyamide PA XY/XZ according to any one of claims 1 to 4, characterized in that it comprises the following steps:
1) inputting the component X, the component Y and the component Z into a polymerization kettle, and heating and stirring in the polymerization kettle to perform dehydration reaction;
2) and after the reaction is finished, discharging the polyamide melt, and carrying out casting belt molding on the melt through a die head, cooling and granulating to obtain the polyamide melt.
6. A polyamide composition comprising:
A. 30-100% by weight of at least one polyamide PA XY/XZ as claimed in claims 1 to 4 or prepared by a process as claimed in claim 5;
B. 0-70% by weight of reinforcing materials and/or fillers;
C. 0-50% by weight of additives and/or other polymers;
wherein components A to C total 100% by weight.
7. A polyamide composition according to claim 6 wherein component B is, at least to some extent, glass and/or carbon fibres selected from short fibres of 2 to 50mm or long continuous fibres, and said glass and/or carbon fibres have a circular or non-circular cross-section.
8. A polyamide composition according to claim 7, wherein component C comprises additives and/or other polymers selected from the group consisting of: impact modifiers, adhesion promoters, compatibilizers, crystallization promoters or retarders, flow aids, lubricants, mold release agents, pigments, plasticizers, stabilizers, processing aids, flame retardants, antistatic agents, conductive additives, polymerization process additives.
9. A plastic article comprising the polyamide composition according to claims 6 to 8, preferably said plastic article is constituted by a molding compound.
10. Parts of the plastic article according to claim 9, in particular in motor vehicles, which are in direct contact with cooling fluids, and/or fluid lines; electronic and particularly portable electronic devices such as mobile phones, smart watches, smart bracelets, portable computers, game consoles, VR glasses, tablets, cameras, etc.; sports equipment; fluid lines for non-automotive use; mechanical engineering; a food utensil; leisure; a toy; the measurement and control technology field.
Technical Field
The present application relates to polyamide articles, and more particularly to a polyamide, a method of making the same, and compositions thereof. The invention also relates to a composition comprising at least one of said polyamides and to articles made from said composition. The invention also relates to the use of the part in the technical fields of motor vehicles, electrical and electronic equipment, sports equipment, fluid pipelines, mechanical engineering, food appliances, leisure, toys, measurement and control.
Background
Polyamide (hereinafter referred to as PA) has excellent mechanical properties, high temperature resistance, wear resistance, oil resistance and processability, has become an indispensable production material in human social life, is widely applied to industries such as electronics, automobiles, buildings, office equipment, machinery, aerospace and the like, and plays an important role in the national economy field.
PA66 and PA6 are varieties with the largest yield in the PA family, have proper production cost and can meet the requirements of common use scenes. However, it also has the disadvantages of poor salt resistance, high water absorption, poor hydrolysis resistance, and the like. Later researchers made up for the deficiencies of PA66 and PA6 by developing long carbon chain PA. The ratio of the number of methylene groups to the number of amido bonds in the main chain of the long carbon chain PA molecule is not less than 7. The long carbon chain PA not only has most general properties of common PA, such as lubricity, wear resistance, compression resistance, easy processability and the like, but also has the characteristics of good toughness and flexibility, low water absorption, good dimensional stability, good salt resistance and hydrolysis resistance, low density and the like. The melting point of long carbon chain PA is reduced to a different extent than PA66, for example, PA612 has a melting point of 218oC, significantly lower than PA 66262oC melting point, so that the temperature resistance of the long carbon chain nylon is obviously reduced relative to that of PA 66.
The salt resistance and chemical resistance of the semi-aromatic polyamide (also called PPA) are obviously higher than those of PA66 and PA6 due to the existence of aromatic rings in a molecular chain. However, since it is as high as 300oThe melting point of about C or higher greatly increases the manufacturing difficulty of the high-temperature-resistant and low-temperature-resistant composite material, and in addition, the high processing temperature puts higher requirements on processing equipment, so that the processing cost and the processing energy consumption are increased, and the application of the high-temperature-resistant and low-temperature-resistant composite material in extrusion and blow molding of parts is also limited.
Disclosure of Invention
In order to overcome the defects of the prior art, the application provides a polyamide and a preparation method thereof, wherein the polyamide has an aliphatic diamine structure with 8-14 carbon atoms, has better chemical resistance relative to PA66, has higher melting point and heat resistance respectively than the conventional long-chain nylon with the same carbon atoms in the main chain, such as PA610, PA612 and the like, has lower processing temperature relative to PPA, reduces the requirement on equipment and energy consumption, and can be used for injection molding, extrusion and blow molding products.
In order to achieve the above object, the present application provides, in one aspect, a polyamide PA XY/XZ polymerized from:
x is an aliphatic diamine containing 8 to 14 carbon atoms and no side chain;
y is a non-pendant aliphatic diacid containing from 4 to 10 carbon atoms and the total number of carbon atoms in X is at least more than 2 than the total number of carbon atoms in Y;
z is an aromatic dicarboxylic acid or/and an aliphatic cyclic dicarboxylic acid;
the XY mole fraction of the polyamide PA XY/XZ is 40-100%, the XZ mole fraction is 0-60%, and the total of the XY and XZ mole contents is 100%. The preferred molar content of XZ is 0 or 20 to 50%. The sum of the molar amounts of all diamines, in the amounts of dicarboxylic acids and diamines forming the polyamide, is substantially equal to the sum of the molar amounts of all dicarboxylic acids. "substantially equal" means a maximum molar excess of 4% for the dicarboxylic acid or diamine, preferably a maximum molar excess of 2% for the dicarboxylic acid or diamine, meaning a molar ratio of dicarboxylic acid to diamine of from 1.04:1 to 1:1.04, preferably a molar ratio of dicarboxylic acid to diamine of from 1.02:1 to 1: 1.02.
The aromatic dicarboxylic acid is selected from one or more of terephthalic acid, 4' -biphenyl dicarboxylic acid and 2, 6-naphthalene dicarboxylic acid, and is preferably terephthalic acid;
the aliphatic cyclic dicarboxylic acid of the present invention is selected from 1, 4-cyclohexanedicarboxylic acid.
In another aspect, the present application provides a method for preparing polyamide, comprising the steps of:
1) adding component X, component Y and component Z to deionized water, pre-salifying, and transferring into a polymerization kettle, or directly transferring into a polymerization kettle, adding any additives, heating and stirring in the polymerization kettle, and dehydrating, such as adding phosphorus-containing acid, such as H, as a suitable catalyst for accelerating polymerization3PO2、H3PO3、H3PO4And salts or organic derivatives thereof;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
In the polymerization reaction, water is efficiently discharged from the reaction system in a short time by heating and stirring and carrying out a dehydration reaction, thereby increasing the reaction rate and promoting the formation of an amide bond to form a desired molecular weight. The relative viscosity and thus the molecular weight can be adjusted in a known manner.
The present invention also provides a polyamide composition comprising:
A. 30-100% by weight of at least one polyamide PA XY/XZ obtained by the process according to claims 1-4;
B. 0-70% by weight of reinforcing materials and/or fillers;
C. 0-50% by weight of additives and/or other polymers;
wherein components A to C total 100%.
Preferably, component B of the composition is, at least to some extent, glass and/or carbon fibers, which may be selected from short fibers of 2-50mm, or continuous long fibers, and the glass and/or carbon fibers have a circular or non-circular cross-section.
Preferably, component C in the composition comprises additives and/or other polymers selected from the group consisting of: impact modifiers, adhesion promoters, compatibilizers, crystallization promoters or retarders, flow aids, lubricants, mold release agents, pigments, plasticizers, stabilizers, processing aids, flame retardants, antistatic agents, conductive additives, polymerization process additives.
The invention also provides a plastic article comprising the aforementioned polyamide composition, preferably said plastic article is comprised of a molding compound. Molded, extruded and blow molded articles can be produced by standard processing techniques for polyamides. For example, the molded parts can be passed through a conventional injection molding machine with a standard 3-stage screw at a temperature of 10 to 60 ℃ above the melting pointoC barrel temperature. The temperature of the die is set to 40-130 deg.CoC, preferably 70 to 100oC。
The plastic part according to the invention can be used in motor vehicles, in particular in components which come into direct contact with cooling fluids, and/or in fluid lines; electronic and particularly portable electronic devices such as mobile phones, smart watches, smart bracelets, portable computers, game consoles, VR glasses, tablets, cameras, etc.; sports equipment; fluid lines for non-automotive use; mechanical engineering; a food utensil; leisure; a toy; the technical field of measurement and control.
Compared with the traditional long-chain nylon such as PA612, the polyamide PA XY/XZ and the composition thereof obtained by the invention have higher melting point, thermal deformation temperature and temperature resistance. Has better chemical resistance performance relative to PA 66.
Detailed Description
The technical solutions of the present application are further described below by the specific embodiments, but the present application is not limited thereto.
The polyamide and the production method thereof according to the present application will be described in detail below with reference to examples, and the raw materials in the examples are all commercially available.
Example 1
A polyamide, the preparation method of which comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of decamethylene diamine and adipic acid with a molar ratio of 1:1, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 20bar and the temperature is 280 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 2
A polyamide, the preparation method of which comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of dodecylamine and adipic acid in a molar ratio of 1:1, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 20bar and the temperature is 280 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 3
A polyamide is polymerized from the following components:
50% of a first component: a mixture of decamethylenediamine and adipic acid in a 1:1 molar ratio;
component two with a molar content of 50%: a mixture of decamethylenediamine and terephthalic acid in a molar ratio of 1: 1;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 25bar and the temperature is 290 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 4
A polyamide is polymerized from the following components:
80% of a first component: a mixture of decamethylenediamine and adipic acid in a 1:1 molar ratio;
20 percent of component II: a mixture of decamethylenediamine and terephthalic acid in a molar ratio of 1: 1;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, adding 1g of phosphoric acid, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 25bar and the temperature is 290 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 5
A polyamide is polymerized from the following components:
70 percent of component one: a mixture of decamethylenediamine and adipic acid in a 1:1 molar ratio;
and the component II with the molar content of 30 percent: a mixture of decamethylenediamine and 1, 4-cyclohexanedicarboxylic acid in a molar ratio of 1: 1;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, adding 0.5g of phosphoric acid, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 25bar and the temperature is 285 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 6
A polyamide is polymerized from the following components:
80% of a first component: a mixture of decamethylenediamine and adipic acid in a 1:1 molar ratio;
20 percent of component II: a mixture of decamethylenediamine and 2, 6-naphthalenedicarboxylic acid in a 1:1 molar ratio;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, adding 1g of phosphoric acid, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 25bar and the temperature is 290 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 7
A polyamide is polymerized from the following components:
80% of a first component: a mixture of decamethylenediamine and adipic acid in a 1:1 molar ratio;
20 percent of component II: a mixture of decamethylenediamine, terephthalic acid and 1, 4-cyclohexanedicarboxylic acid in a molar ratio of 1:0.5: 0.5;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, adding 1g of phosphoric acid, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 25bar and the temperature is 290 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 8
A polyamide is polymerized from the following components:
80% of a first component: a mixture of dodecylamine and adipic acid in a 1:1 molar ratio;
20 percent of component II: a mixture of dodecylamine and terephthalic acid in a 1:1 molar ratio;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, adding 1g of phosphoric acid, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 23bar and the temperature is 285 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Example 9
A polyamide is polymerized from the following components:
80% of a first component: a mixture of dodecylamine and adipic acid in a 1:1 molar ratio;
20 percent of component II: a mixture of dodecylamine, terephthalic acid and 1, 4-cyclohexanedicarboxylic acid in a molar ratio of 1:0.5: 0.5;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, adding 1g of phosphoric acid, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 23bar and the temperature is 285 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Comparative example 1
A polyamide, the preparation method of which comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of hexamethylene diamine and sebacic acid with a molar ratio of 1:1, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 20bar and the temperature is 280 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Comparative example 2
A polyamide, the preparation method of which comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of hexamethylene diamine and dodecanoic acid with the molar ratio of 1:1, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 20bar and the temperature is 280 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Comparative example 3
A polyamide is polymerized from the following components:
80% of a first component: a mixture of hexamethylenediamine and sebacic acid in a molar ratio of 1: 1;
20 percent of component II: a mixture of hexamethylenediamine and terephthalic acid in a molar ratio of 1: 1;
the preparation method comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of a component I and a component II, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 25bar and the temperature is 290 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Comparative example 4
A polyamide, the preparation method of which comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of decamethylene diamine and sebacic acid with a molar ratio of 1:1, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 20bar and the temperature is 240 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
Comparative example 5
A polyamide, the preparation method of which comprises the following steps:
1) adding 10kg of deionized water into a 50L automatic control polymerization kettle with a stirrer, then adding 25kg of a mixture of dodecylamine and dodecanoic acid with a molar ratio of 1:1, and carrying out dehydration reaction under the conditions that the pressure of the polymerization kettle is 18bar and the temperature is 220 ℃;
2) after the reaction, nitrogen is injected to discharge the moisture generated by the reaction, then the polyamide melt is discharged under pressure, and the melt is formed by die head casting belt and is cooled and cut into particles to obtain the polyamide melt.
1. Test method
The following test methods are used within the scope of the present application:
relative viscosity according to ISO 307 (2007) at 20oThe relative viscosity is measured at C, 0.5g of polymer pellets are weighed into 100ml of m-cresol and the relative viscosity RV is calculated according to chapter 11 of the standard
Melting points were measured according to ISO 11357-3-2011 plastic-Differential Scanning Calorimetry (DSC) method and melting peaks were recorded.
Heat resistance was tested according to the Heat distortion temperature test method under ISO 75-2 load and the heat distortion temperature after 33% glass fiber reinforcement was recorded.
Tensile Strength according to ISO527 at 23oThe bars of ISO/CD 3167A 1 type 170x20/10x4mm were tested at C, and the flexural strength and flexural modulus were tested on the same bars using the ISO178 standard.
The mixing of polyamide and glass fibres may be carried out by standard processing techniques for polyamides, for example in the present invention using a 48 aspect ratio twin screw extruder with a screw diameter of 30mm and an extruder barrel temperature settingIs 20 higher than the melting point of polyamideoAnd C, cooling the mixed material strips through a water tank and then pelletizing.
Notched impact strength of 23 ℃ according to ISO179/keU vs ISO/CD 3167B 1 type 80x10x4mm barsoC test
TABLE 1 results of respective performance tests of examples 1 to 4 and comparative examples 1 to 3
As can be seen from Table 1, the polyamide according to the present invention has a higher melting point and heat resistance than conventional long carbon chain polyamides. Comparative example 1, in which the PA106 of example 1 has the same number of carbon atoms in the main chain, the PA610 of example 1 has a melting point of 19. sup. thoC, heat distortion temperature is 20 ℃ higheroC. The melting point of the polyamide can be further improved after terephthalic acid, 1, 4-cyclohexanedicarboxylic acid and 2, 6-naphthalenedicarboxylic acid are introduced in examples 3 to 7, and the melting point is significantly lower than that of the conventional PPA 300oThe melting point of C is about, so that the requirement on processing equipment is reduced, and the energy consumption is reduced. For example, PA106/10T (80 mol% 106: 20 mol% 10T; where T represents terephthalic acid) in example 4 has a melting point 46 higher than that of comparative example 3 PA610/6T (80 mol% 610: 20 mol% 6T; where T represents terephthalic acid) having the same number of carbon atoms in the main chainoC, high heat distortion temperature of 42 DEG CoC. The PA126 of example 2 has a melting point 10 higher than that of the PA612 of comparative example 2, which has the same number of carbon atoms in the main chainoC, high heat distortion temperature 13oC. The melting point of the polyamide can be further increased after the introduction of terephthalic acid and 1, 4-in examples 8 to 9.
It should be noted that the above specific examples are only for illustrating the present application and not for limiting the scope of the present application, and after reading the present application, those skilled in the art should be able to modify the various equivalent forms of the present application, such as replacing the content of each component, replacing the specific components of aliphatic diamine, aromatic diacid, etc., adjusting the preparation parameters, etc., within the scope of the present application as defined in the appended claims.